I use bitcoin as currency and i never sell my bitcoin, but i prefer to use bitcoin when price is rising
So, how about you?
Until you spend your bitcoin( you says that you prefer to spend when the price is high) then means that through this time you are pretty much investing in bitcoin and sell them for a higher price. I use bitcoin as an investment and as a currency, it's a good to have a good backup(savings) in bitcoin because one day you will probably need for these money. I use also as a currency because most of the digital things can be bought through bitcoin.